/*
 * Copyright (C) 2012 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.zxing.client.android.camera.open;

import android.hardware.Camera;
import android.os.Build;
import android.util.Log;

public final class OpenCameraInterface {

	private static final String TAG = OpenCameraInterface.class.getName();

	private OpenCameraInterface() {
	}

	/**
	 * Opens a rear-facing camera with {@link Camera#open(int)}, if one exists,
	 * or opens camera 0.
	 */
	public static Camera open() {
		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD) {
			int numCameras = Camera.getNumberOfCameras();
			if (numCameras == 0) {
				Log.w(TAG, "No cameras!");
				return null;
			}

			int index = 0;
			while (index < numCameras) {
				Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
				Camera.getCameraInfo(index, cameraInfo);
				if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_BACK) {
					break;
				}
				index++;
			}

//			Camera camera;
//			if (index < numCameras) {
//				Log.i(TAG, "Opening camera #" + index);
//				camera = Camera.open(index);
//			} else {
//				Log.i(TAG, "No camera facing back; returning camera #0");
//				camera = Camera.open(0);
//			}
			
			Camera camera;
			if (index < numCameras) {
				Log.i(TAG, "Opening camera #" + index);
			} else {
				Log.i(TAG, "No camera facing back; returning camera #0");
				index = 0;
			}
			camera = Camera.open(index);

			//旋转为竖屏
			if (camera != null) {
				Camera.CameraInfo info = new Camera.CameraInfo();
				android.hardware.Camera.getCameraInfo(index, info);

				final int degrees = 0;
				int result;
				if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
					result = (info.orientation + degrees) % 360;
					result = (360 - result) % 360; // compensate the mirror
				} else { // back-facing
					result = (info.orientation - degrees + 360) % 360;
				}
				camera.setDisplayOrientation(result);
			}

			return camera;
		} else {
			return Camera.open();
		}
	}
}
